2001 Volume 44 Issue 1 Pages 64-70
The multiple strata plasticity model, which was presented in the previous paper by introducing the tensor Q expressing the activating state of slip systems in the polycrystalline metal, has been developed with a new internal state factor B5. This factor B5 denotes the ratio of the grains with activating slip systems greater than five to the total grains. The variation features of B5 and Q can be computationally evaluated with a virtual polycrystalline specimen. The microstructure state, such as dislocation density can be reflected in the internal structure variable A in this model. The relationship between B5 and A has been examined on the tensile flow curve of pure copper. As a result, a simple formula connecting A with B5 was determined. Moreover, it has been clarified that this formula is applicable for describing the plastic deformations under other proportional loadings.